In the late forties and the first half of the fifties, one of the areas of work of the team of the Experimental Design Bureau, headed by Sergey Vladimirovich Ilyushin, was the creation of jet bombers. They were distinguished by one characteristic feature - high combat and operational efficiency, achieved with minimal geometric dimensions and the smallest mass of the machine. The first and most famous of them is the IL-28 front-line jet bomber. His project was developed at the end of 1947. Well armed and protected, he possessed high flight performance, good stability and controllability. The maximum speed is 900 km / h. With a normal combat load of 1000 kg (maximum - 3000 kg), the flight range was 2400 km. The IL-28 was distinguished by a record, exceptionally low cost in serial production: the complexity of building a 22-ton bomber was close in this indicator to what a 5-ton fighter required. It was also distinguished by its lightness and simplicity in mastering the flight and technical personnel.
S.V. Ilyushin received a task to develop a medium-range high-speed jet bomber (with twice the maximum combat load and flight range than Il-28). Because Ilyushin did not want to take a greater risk, the aircraft, which became known as the Il-46, conceived as an accurate aerodynamic enlargement of the front bomber type Il-28 ( Beagle). Then they made an unusual decision: when creating the IL-46(as it was called) to build two different experimental models for a full-scale comprehensive comparative assessment: one with a layout close to the Il-28, with a straight wing, and the second with a swept one.
A plane with normal flight weight and 3,000 kg bombs had to have a combat radius of up to 1,500 km. When overloaded, the mass of bombs increased to 5000 kg, and the radius increased to 2500 km. Destruction of targets on the territory of the enemy should have been carried out in a range of heights from 3000 m to the practical ceiling in any meteorological conditions with strong opposition of the enemy’s air defense forces. The efforts of the OKB team spent on the development of the two previous machines were not in vain. Interesting design developments and calculations performed on the IL-48 and IL-42 aircraft were fully used in the design of the new bombardment IL-46 and its modifications IL-46C.
Difficulties with the choice of wing configuration, which took place at the initial stage of the IL-30 design, led to the decision to design and build a new aircraft in two versions - with a direct and swept wing. Studies of the behavior of the direct wing, performed on the Il-28 plane, provided the necessary safe speed and made it possible to increase the flight range. Sketch design of the first option S.V. Ilyushin approved in the fall of 1951. The pilot, navigator and gunner-radio operator were stationed in two airtight cabins on ejected seats. Defensive weapons also remained unchanged.
The landing gear scheme, which was completely borrowed from IL-48, provided the aircraft with confident movement along uneven field airfields. The ability to operate Il-46 aircraft on unpaved runways caused the construction of a unique landing gear structure. A separate wheel was attached to each suspension strut of the main supports. During the landing gear cleaning, the racks moved in different directions: the outer rack with the wheel retracted forward, and the inner rack with the wheel - backward in flight. The wheels rotated at an angle of 90 ° and entered the fairings of the lower parts of the nacelles under the exhaust pipes. The main wheels were unwound before landing by the aircraft’s hydraulic system.
At the very end of 1951, the second version of the swept wing aircraft was approved. The second prototype Il-46S ("C" - with a flight speed of 1000 km / h was supposed to have a wing with a sweep of 35 °. Its main feature was a thickened root part for strength and rigidity and placement of a significant part of the fuel. The first experimental one, like on the Il-28, all fuel was housed in the fuselage. The swept wing has slightly worse load-bearing properties than the direct one. Therefore, its area and weight for the Il-46C were increased. The sketch design was approved by Ilyushin in December 1951. according to preliminary calculations should be able to fly at about 1,000 km / h. In contrast, the speed of the model Il-46, which counted with a straight wing, should range from 900 to 925 km / h.
The first flight of a direct-wing aircraft was performed on March 3, 1952 by V.K. Kokkinaki, who noted the good longitudinal and track stability of the aircraft, which was easily balanced over the entire speed range until the loads were completely removed from the controls. During the tests, a speed of 928 km / h was achieved. The 5000 kg bomb load dropped halfway allowed the aircraft to reach a flight range of 4845 km. After the state tests were prototype of this machine equipped with more powerful 5 750 kp Al-5F engines. This type of engine was nothing but a modification of the Al-5 engine with the installation of an afterburner chamber. This change in the propulsion system made it possible to increase the maximum take-off mass to 53,788 kg. Even later, the maximum take-off weight of the prototype aircraft type Il-46 increased to 54 823 kg. This allowed the installation of new undercarriage wheels.
To enter the jet successor piston bomber type Tu-4 (Bull ) meanwhile, on his own initiative also responded AN Tupolev, with a type of Tu-88. It was not only equipped with an arrow wing and tail surfaces, but also noticeably stronger 8 750 kp engines type AM-3. Thanks to all the aircraft type Il-46 significantly exceeded the speed (almost 100 km / h), ceiling (about 1 500 m) and the carrying capacity of bombs (about 3 000 kg). Before the Il-46, but had the upper hand in firepower defensive armament. Part of the defensive armament of the aircraft type Tu-88 happened just seven 23 mm cannons, which provided circular defense, while the Il-46 was equipped with only four cannons of the same caliber. Operational modification of the aircraft type Tu - 88, however, became known Tu - 16 (Badger A).
Despite the positive assessment obtained during the state tests: "The IL-46 jet bomber, in terms of its flight performance and combat capabilities, basically satisfies its purpose in accordance with the tactical and technical requirements of the Air Force and can fulfill the tasks of a front-line and long-range bomber," the final act of these tests was already another verdict: "In connection with that the Tu-16 aircraft was launched into serial production, it is not practical to launch this aircraft into serial production. ”
In April 1953, by order of the government, all work on the Il-46 aircraft was discontinued. It would be an ungrateful occupation to look for the perpetrators of what happened. The reason could be government tasks following one after another, different in names of aircraft, but in essence, identical in content, constantly changing the subject of work of OKB S.V. Ilyushin, which allowed the Tu-16 to be the first to get into state tests. Or maybe the fault was the indecision of the Chief Designer when he chose the direct wing on the first version of the machine. Indeed, in aviation, as in life, “fashion” is of great importance.
|Wing area, m2||105.00|
|engine's type||2 turbojet engine AL-5|
|Thrust, kgf||2 x 5000|
|Speed km / h|
|Flight range, km||4970|
|Practical ceiling, m||12700|
|Radar||bomber-navigation pulse doppler radar type PSBNM-15 with a detection range of 80 km and warning radar rear type PRS-1 Argon * ( 'Bee Hind' ). Radar type PSBNM-15 is used for searching and tracking large ground targets and its installation is located inside a large protruding dielectric cove, located on the belly of the fuselage, directly behind the nose landing gear shaft. Egg-shaped radar case type PRS-1, which is used for searching and tracking air targets in the rear, is in turn attached, with the help of a slim beveled pylon, to the "roof" cockpit "tail" shooter.|
|sighting Equipment||one optical bombardment sight type OPB-6SR (its installation is located behind the front flat oval window of the bow of the navigator),|
|Join the GlobalSecurity.org mailing list|